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G B Wilson

Publications and source records attributed to G B Wilson.

At least 37 records · Page 2Linked to original sources

Effects of dialyzable leukocyte extracts (DLEs) with transfer factor activity on leukocyte migration in vitro. III. Characterization of the antigen-independent migration inhibition factor in DLEs as a neutrophil immobilizing factor.

In earlier evaluations of the agarose LMI assay as an in vitro test for studying the nature and mechanism of action of TF, we reported the existence of a component in human DLEs which caused noncytotoxic inhibition of the random migration of human PMNs. The LMI was not dependent on the stimulation of viable mononuclear leukocytes by antigen or mitogen to effect the release of mediators of cellular immunity such as LIF; rather, the LMI was promoted by the direct action of a preexisting component in DLEs on PMNs. We now present evidence that this "antigen-independent" LMI activity in DLE'S is similar to a NIF shown previously by Goetzl and co-workers to be present in acid extracts of leukocytes and to be released by phagocytosing PMNs. The comparison is drawn from several parameters: (1) cellular origin, (2) molecular weight, (3) target cell, (4) susceptibility to inactivation by heating or by incubation with pronase, trypsin, or chymotrypsin, and (5) ability to cause noncytotoxic inhibition of random migration or chemotaxis of PMNs.

Animals↗

Effects of dialyzable leukocyte extracts with transfer factor activity on leukocyte migration in vitro. 1. Antigen-dependent inhibition and antigen-independent inhibition and enhancement of migration.

The effects of DLE containing TFd activity from immune human donors on PBL, obtained from individuals nonresponsive to either PPD or Cocci antigen, were evaluated in vitro by the agarose LMl technique. Several different preparations of DLE were employed to evaluate the specificity and reproducibility of the effects: (1) from donors skin test positive to PPD but negative to Cocci, (2) from donors skin test negative to PPD but positive to Cocci, (3) from donors skin test positive to both antigens, and (4) from donors skin test negative to both antigens. With PBL from other human donors used as target cells in the direct agarose LMi technique, three types of effects were demonstrated for all preparations of DLE: (1) antigen-dependent specific LMl, (2) antigen-independent or nonspecific LMl, and (3) antigen-independent enhancement of migration. The demonstration of each activity was found to depend on the concentration of DLE used and the time allowed for migration. In experiments employing purified PMN and MNL as target cells and a two-step indirect LMl assay, it was shown that the antigen-independent effects resulted from the direct of components in DLE on PMN. The antigen-independent inhibition was shown not to result from toxic effects of DLE. It was produced by DLE but not by dialyzable liver or skin extracts when tested using an amount equivalent to DLE as judged by the absorbance at 260 and 280 nm. The antigen-dependent LMl was found to require secretion of a soluble mediator of molecular weight near 69,000, believed to be LMl. Our results indicate that the agarose LMl technique is a useful in vitro assay for studies of the mechanism of action of components in DLE which can specifically convert nonimmune lymphocytes to a measurable antigen-sensitive state (i.e., transfer factor). The antigen-independent effects of DLE may be responsible in part for previously reported nonspecific beneficial effects of DLE when used in immunotherapy.

Antigens↗

Effects of dialyzable leukocyte extracts with transfer factor activity on leukocyte migration in vitro. II. Separation and partial characterization of the components in DLE producing antigen-dependent and antigen-independent effects.

Previous studies have shown that DLEs with TFd activity produce both Ag-dependent specific effects (mediated by TFd) and Ag-independent effects on CMl as demonstrated in vitro by agarose LMl. In the present study, Sephadex G-25 gel filtration provided a simple method for separating the DLE components responsible for each effect into distinct fractions. Ag-independent LMl was produced predominantly by Sephadex fraction l, of MW greater than 5000. The active components, further purified on Bio-Gel P-10, were shown to be of MW 14,000 to 17,000 and to contain both polypeptide and ribonucliotide material. The Ag-independent LMl activity was stable to heating at 56 degrees C for 30 min but was partially destroyed at 80 degrees C for 30 min, and the responsible components were shown to act on PMN directly. Ag-independent ELM was produced exclusively by material in Sephadex G-25 fraction V and also acted directly on PMN, whereas the Ag-dependent specific LMl activity was found predominantly in fraction lVb and to a lesser extent in fraction V and could not be detected in a direct assay using only PMN. In addition, a new activity, designated "Ag-dependent ELM activity," which caused increased migration in the presence of Ag, was found in Sephadex fraction lVa. This latter activity might mask the Ag-dependent LMl activity in fraciton lVb. Bio-Gel P-2 chromatography separated the components producing Ag-dependent and Ag-independent effects in fraction V into two separate subfractions (Va and Vb) of MW 1100 to 2000 and less than 900. The activity in fraction lVb eluted at a position identical to that of the components in fraction Va on Bio-Gel P-2. Fractions Va and Vb contained both polypeptide and ribonucleotide material. The Ag-dependent specific LMl or TFd activity was found to be partially inactivated at 56 degrees C and completely destroyed at 80 degrees C. The components responsible for this TFd activity were further purified by HPLC on ODS resin. The TFd activity was mediated by components with retention times much greater than that of adenosine 3'-monophosphate. The active fraction was composed of both polypeptide and ribonucleotide material but did not contain deoxyribonucleotides.

Antigens↗

Immunofixation after electrofocusing: improved method for specific detection of serum proteins with determination of isoelectric points. I. Immunofixation print technique for detection of alpha-1-protease inhibitor.

An improved method is described for direct localization of human serum proteins in polyacrylamide gel with simultaneous determination of their isoelectric points (pI). The technique employs isoelectric focusing in thin-layer polyacrylamide gels to separate the serum proteins and the pH gradient is read at 4 degrees C with a dual-membrane surface microelectrode. Subsequently, the desired proteins are localized by immunofixation in the gel or by immunofixation-printing onto cellulose acetate strips soaked in specific antiserum. No sectioning of the electrofocused gel is necessary, and the entire technique can be completed in less than 14 h. When this method is applied to the detection of the genetic variants of alpha-1-antitrypsin (alpha-1-protease inhibitor) (A1Pi system), the results indicate that it can be used to specifically localize serum proteins whose pI's differ by as little as 0.01 pH units. The resolution afforded is especially evident in the analysis of A1Pi M variants.

Blood Proteins↗

Studies on cystic fibrosis using isoelectric focusing. III. Correlation between cystic fibrosis protein and ciliary dyskinesia activity in serum shown by a modified rabbit tracheal bioassay.

We have developed a modified rabbit tracheal bioassay for use in investigating a possible correlation between cystic fibrosis protein (CFP) and ciliary dyskinesia factor (CDF) in human serum. The bioassay requires high standards of tissue selection, and all epithelial tissue must be free of underlying connective tissue. When serum samples were collected and processed carefully and warmed to 37 degrees before assay, CDF could be reliably detected in 31 of 31 sera from cystic fibrosis (CF) homozygotes or obligate heterozygotes in 35 min or less without prior fractionation or concentration of sera, whereas 13 of 14 normal control sera were nonreactive. CDF-positive serum reacts in three consecutive phases: (1) initial increase in ciliary beat frequency, (2) ciliary dyskinesia, and (3) tissue destruction with extrusion of single ciliated cells, mucus, and debris. Our results confirm the association of CDF with cystic fibrosis. The bioassay is not specific for CF, however, when whole sera are bioassayed, since serum from several patients with bronchial asthma also caused ciliary dyskinesia. However, this finding need not preclude using rabbit tracheal ciliated epithelial tissue as an assay for following the purification of CDF. Isoelectric focusing showed that the presence or absence of CFP corresponded with that of dyskinesia activity in all sera tested except for the active samples from seven asthma patients, which were negative for CFP. The results indicate that CFP and CDF may be identical or closely related markers for the CF gene, and suggest that the activity detected by the rabbit tracheal bioassay in sera from patients with asthma and other diseases probably is caused by a substance different from a CF-specific CDF.

Animals↗